Effect of LiCl and non-ionic surfactant on morphology of polystyrene electrospun nanofibers

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Delaram Fallahi ◽  
Mehdi Rafizadeh ◽  
Naser Mohammadi ◽  
Behrooz Vahidi
Keyword(s):  
Electron Microscopy ◽  
Surface Tension ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Ionic Surfactant ◽  
Electrospun Fibers ◽  
Electrospinning Technique ◽  
Solution Surface ◽  
Solution Conductivity ◽  
Scanning Electron

AbstractPolystyrene fibers were produced by the electrospinning technique. The effects of solution conductivity, surface tension and concentration on morphology and average diameter of electrospun fibers were investigated by scanning electron microscopy (SEM). Solutions of 12, 10, 8, 6% (w/v) polystyrene in dimethylformamide were prepared. Lithium Chloride and a non-ionic surfactant were used to change the conductivity and surface tension of the solutions, respectively. The results indicate that increasing the solution conductivity eliminates the bead formation and increases the fiber diameters. By addition of salt, fine and consistent fibers could be produced from electrospinning of 8% (w/v) PS/DMF solution. Adding 0.1% surfactant reduces the solution surface tension and results in smaller beads and higher fiber diameters. By increasing the amount of surfactant to 0.3%, big beads and thinner fibers are produced.

scholarly journals Synthesis and Characterization of Stable and Binder-Free Electrodes of TiO2Nanofibers for Li-Ion Batteries

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Phontip Tammawat ◽  
Nonglak Meethong
Keyword(s):  
Electron Microscopy ◽  
Electrochemical Impedance ◽  
Coulombic Efficiency ◽  
Electronic Conductivity ◽  
Lithium Ion ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Reversible Capacity ◽  
Electrospinning Technique ◽  
Binder Free

An electrospinning technique was used to fabricate TiO2nanofibers for use as binder-free electrodes for lithium-ion batteries. The as-electrospun nanofibers were calcined at 400–1,000°C and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). SEM and TEM images showed that the fibers have an average diameter of ~100 nm and are composed of nanocrystallites and grains, which grow in size as the calcination temperature increases. The electrochemical properties of the nanofibers were evaluated using galvanostatic cycling and electrochemical impedance spectroscopy. The TiO2nanofibers calcined at 400°C showed higher electronic conductivity, higher discharge capacity, and better cycling performance than the nanofibers calcined at 600, 800, and 1,000°C. The TiO2nanofibers calcined at 400°C delivered an initial reversible capacity of 325 mAh·g−1approaching their theoretical value at 0.1 C rate and over 175 mAh·g−1at 0.3 C rate with limited capacity fading and Coulombic efficiency between 96 and 100%.

scholarly journals Synthesis and mechanical characterization of a non-woven nanofiber by the electrospinning technique

DYNA ◽  
2019 ◽  
Vol 86 (209) ◽  
pp. 64-72
Author(s):  
Edwin Edgardo Espinel Blanco ◽  
Nelson Escobar-Mora ◽  
Lina Marcela Hoyos-Palacio ◽  
Martin Fabián Sarmiento-Gaviria
Keyword(s):  
Electron Microscopy ◽  
Mechanical Characterization ◽  
Average Diameter ◽  
Electrospinning Technique ◽  
Acid Ratio ◽  
Nanostructured Polymer ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Scanning Electron

A non-woven nanofiber or polymeric cover is synthesized with nylon-6 as the base polymeric material. Different acid relationships (formic/acetic) were tested in the electrospinning equipment, until defining by macroscopic observations and SEM Scanning Electron Microscopy analysis the adequate acid ratio 3:2 and the average diameter of the nanofibers in 350nm, defining the parameters to operate the electrospinning. According to ASTM D 882 standard, the Tensile Strength was calculated for stresses applied horizontally and vertically to the direction of the nanofibers. With the standards ASTM D 7490 and ASTM G-15 the wettability was determined by measuring the contact angle, finding that it has hydrophilic properties with high wettability, adhesiveness and surface energy. Nanostructured polymer covers can be used for biological isolation in health care areas, as a protective barrier to control the spread of infections. 

Fabrication of Nanofibers via Crater-Like Electrospinning

2011 ◽  
Vol 332-334 ◽  
pp. 1257-1260 ◽  
Author(s):  
Yuan Yuan Wang ◽  
Yong Liu ◽  
Wei Liang ◽  
Ming Ma ◽  
Rui Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Fiber Diameter ◽  
Average Diameter ◽  
Diameter Distribution ◽  
Excellent Performance ◽  
Electrospinning Technique ◽  
Multiple Jets ◽  
Medical Materials ◽  
Scanning Electron

Nanofibers, with its excellent performance, have played a significant role in the fields of filtration materials, medical materials, biomaterials, etc. In this work, a novel electrospinning technique, carter-like electrospinning, was presented and used to produce nanofibers. Multiple jets, which have the potential to increase the yield of nanofibers, were found in our experiments. The geometric properties, such as fiber diameter, diameter distribution, and surface morphology of the produced Nanofibers via this process, were characterized using a field emission scanning electron microscopy (FESEM). The results showed that the diameters of nanofibers ranged from several nanometers to one micron, and the nanofibers had average diameter of 84-550nm.

Electrospinning of Pullulan Nanofibers for Food Package Materials

2013 ◽  
Vol 821-822 ◽  
pp. 1321-1325 ◽  
Author(s):  
Yong Fang Qian ◽  
Lai Jiu Zheng ◽  
Ruo Yuan Song ◽  
Bing Du
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Normal Distribution ◽  
Electrospun Nanofibers ◽  
Solution Concentration ◽  
Electrospun Fibers ◽  
Food Package ◽  
Water As Solvent ◽  
Package Materials ◽  
Scanning Electron

Electrospinning is a process that fabricates continuous fibers with diameters in the nanoto micron range. Pullulan with different concentrations were successfully electrospun into nanofibers with water as solvent in this study. We have evaluated the effects of solution concentration on the morphology of the fibers. The morphologies of the nanofibrous mats were examined by Scanning Electron Microscopy (SEM). With increasing the solution concentration, the electrospun nanofibers changed from beaded nanofibers to smooth nanofibers, meanwhile, the average diameters of electrospun pullulan nanofibers increased from 44nm, 89nm, 136nm, 172nm to 219nm when the solution concentration changed from 12, 15, 20, 25 to 30 wt%. The distribution of electrospun fibers is normal distribution. The electrospun nanofibrous mats will be a promising food package material.

Preparation of Ultrafine Poly(ε-Caprolactone) Fibers Containing Silver Nanoparticles via Electrospinning Method

2011 ◽  
Vol 332-334 ◽  
pp. 1235-1238 ◽  
Author(s):  
Yong Tang Jia ◽  
Qing Qing Liu ◽  
Xiang Ying Zhu
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Ag Nanoparticles ◽  
Average Diameter ◽  
Contact Angles ◽  
Electrospun Fibers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrospinning Method ◽  
Scanning Electron

Electrospun poly(ε-caprolactone) (PCL) fibers containing silver nanoparticles were successfully prepared from PCL solutions added silver collide. The silver collide were obtained by N, N-dimethylformamide (DMF) reducing silver nitrate (AgNO3). The effects of PCL concentration and the content of silver nanoparticles on composite fibers morphology were characterized by field-emission scanning electron microscopy (FESEM). The existence of Ag nanoparticles on the electrospun fibers was approved by X-Ray diffraction (XRD). Simultaneously, the contact angles of fiber membranes were measured. The results indicated that uniform fibers were obtained when PCL concentration was 9wt%, the average diameter of fiber was significantly decreased as increasing the amount of silver collide, and Ag nanoparticles were successfully incorporated into the PCL fibers.

The Critical Point Drying Method Applied to Scanning Electron Microscopy of L-929 Cells

1970 ◽  
Vol 28 ◽  
pp. 278-279
Author(s):  
Charles TurnbiLL ◽  
Delbert E. Philpott
Keyword(s):  
Electron Microscopy ◽  
Carbon Dioxide ◽  
Surface Tension ◽  
Critical Point ◽  
Freeze Drying ◽  
Attractive Alternative ◽  
Crystal Formation ◽  
Critical Point Drying ◽  
Time Required ◽  
Scanning Electron

The advent of the scanning electron microscope (SCEM) has renewed interest in preparing specimens by avoiding the forces of surface tension. The present method of freeze drying by Boyde and Barger (1969) and Small and Marszalek (1969) does prevent surface tension but ice crystal formation and time required for pumping out the specimen to dryness has discouraged us. We believe an attractive alternative to freeze drying is the critical point method originated by Anderson (1951; for electron microscopy. He avoided surface tension effects during drying by first exchanging the specimen water with alcohol, amy L acetate and then with carbon dioxide. He then selected a specific temperature (36.5°C) and pressure (72 Atm.) at which carbon dioxide would pass from the liquid to the gaseous phase without the effect of surface tension This combination of temperature and, pressure is known as the "critical point" of the Liquid.

Isolasi Dan Karakterisasi Bentonit Alam Menjadi Nanopartikel Monmorillonit

2018 ◽  
Vol 3 (1) ◽  
pp. 12 ◽  
Author(s):  
Zaimahwati Zaimahwati ◽  
Yuniati Yuniati ◽  
Ramzi Jalal ◽  
Syahman Zhafiri ◽  
Yuli Yetri
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Surface Morphology ◽  
Average Diameter ◽  
Particle Size Analyzer ◽  
Ft Ir ◽  
Scanning Electron ◽  
Sedimentation Processes

<p>Pada penelitian ini telah dilakukan isolasi dan karakterisasi bentonit alam menjadi nanopartikel montmorillonit. Bentonit alam yang digunakan diambil dari desa Blangdalam, Kecamatan Nisam Kabupaten Aceh Utara.  Proses isolasi meliputi proses pelarutan dengan aquades, ultrasonic dan proses sedimentasi. Untuk mengetahui karakterisasi montmorillonit dilakukan uji FT-IR, X-RD dan uji morfologi permukaan dengan Scanning Electron Microscopy (SEM). Partikel size analyzer untuk menganalisis dan menentukan ukuran nanopartikel dari isolasi bentonit alam. Dari hasil penelitian didapat ukuran nanopartikel montmorillonit hasil isolasi dari bentonit alam diperoleh berdiameter rata-rata 82,15 nm.</p><p><em>In this research we have isolated and characterized natural bentonite into montmorillonite nanoparticles. Natural bentonite used was taken from Blangdalam village, Nisam sub-district, North Aceh district. The isolation process includes dissolving process with aquades, ultrasonic and sedimentation processes.  The characterization of montmorillonite, FT-IR, X-RD and surface morphology test by Scanning Electron Microscopy (SEM). Particle size analyzer to analyze and determine the size of nanoparticles from natural bentonite insulation. From the research results obtained the size of montmorillonite nanoparticles isolated from natural bentonite obtained an average diameter of 82.15 nm.</em></p>

Characterization of Al65.0Cu32.9Co2.1 Alloy Containing Nanofibres

2012 ◽  
Vol 186 ◽  
pp. 212-215
Author(s):  
Jacek Krawczyk ◽  
Włodzimierz Bogdanowicz ◽  
Grzegorz Dercz ◽  
Wojciech Gurdziel
Keyword(s):  
Electron Microscopy ◽  
Average Diameter ◽  
Chemical Compositions ◽  
X Ray ◽  
Transmission Electron ◽  
Orthogonal Set ◽  
T Phase ◽  
Terminal Area ◽  
Scanning Electron

Microstructure of terminal area of Al65Cu32.9Co2.1ingots (numbers indicate at.%), obtained via directional solidification was studied. Scanning Electron Microscopy, Transmission Electron Microscopy and X-ray powder diffraction were applied. Point microanalysis by Scanning Electron Microscope was used for examination of chemical compositions of alloy phases. It was found that tetragonal θ phase of Al2Cu stoichiometric formula was the dominate phase (matrix). Additionally the alloy contained orthogonal set of nanofibres of Al7Cu2Co T phase with the average diameter of 50-500 nm and oval areas of hexagonal Al3(Cu,Co)2H-phase, surrounded by monoclinic AlCu η1phase rim. Inside some areas of H-phase cores of decagonal quasicrystalline D phase were observed.

scholarly journals Mechanical and Dielectric Properties of Aligned Electrospun Fibers

Fibers ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 4
Author(s):  
Blesson Isaac ◽  
Robert M. Taylor ◽  
Kenneth Reifsnider
Keyword(s):  
Dielectric Properties ◽  
Dielectric Property ◽  
Electrospun Nanofibers ◽  
Cold Drawing ◽  
General Interest ◽  
Electrospun Fibers ◽  
Energy Storage Devices ◽  
Electrospinning Technique ◽  
Specific Strength ◽  
Aligned Nanofibers

This review paper examines the current state-of-the-art in fabrication of aligned fibers via electrospinning techniques and the effects of these techniques on the mechanical and dielectric properties of electrospun fibers. Molecular orientation, system configuration to align fibers, and post-drawing treatment, like hot/cold drawing process, contribute to better specific strength and specific stiffness properties of nanofibers. The authors suggest that these improved, aligned nanofibers, when applied in composites, have better mechanical and dielectric properties for many structural and multifunctional applications, including advanced aerospace applications and energy storage devices. For these applications, most fiber alignment electrospinning research has focused on either mechanical property improvement or dielectric property improvement alone, but not both simultaneously. Relative to many other nanofiber formation techniques, the electrospinning technique exhibits superior nanofiber formation when considering cost and manufacturing complexity for many situations. Even though the dielectric property of pure nanofiber mat may not be of general interest, the analysis of the combined effect of mechanical and dielectric properties is relevant to the present analysis of improved and aligned nanofibers. A plethora of nanofibers, in particular, polyacrylonitrile (PAN) electrospun nanofibers, are discussed for their mechanical and dielectric properties. In addition, other types of electrospun nanofibers are explored for their mechanical and dielectric properties. An exploratory study by the author demonstrates the relationship between mechanical and dielectric properties for specimens obtained from a rotating mandrel horizontal setup.

scholarly journals Fabrication of Drug-Loaded Starch-based Nanofibers via Electrospinning Technique

2020 ◽  
Vol 11 (3) ◽  
pp. 10801-10811
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Poly Vinyl Alcohol ◽  
Loading Capacity ◽  
Sago Starch ◽  
Electrospinning Technique ◽  
Blending Process ◽  
Operation Parameters ◽  
Optimized Conditions ◽  
Scanning Electron

This paper reported the fabrication of starch-based nanofibers derived from various weight ratios (w:w) of native sago starch (SS) and poly (vinyl alcohol) (PVA) (0:100, 1:100, 3:100, and 5:100) using the electrospinning technique. The effects of electrospinning operation parameters on the surface morphology of SS/PVA nanofibers were observed by using Scanning Electron Microscopy (SEM). The smooth and bead-free SS/PVA nanofibers with fiber diameters within the range of 90 nm to 150 nm were produced under the optimized conditions. The paracetamol (PCM) was encapsulated into the SS/PVA nanofibers via the blending process. The SS/PVA nanofibers exhibited a maximum PCM loading capacity of 0.9573 mg.mg-1, and PCM was observed to release out from SS/PVA nanofibers slowly and steadily for 72 hours.

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